Lathe dog



Aug. 26 1924.

A. VALTMAN LATHE DOG Filed July 28. 1925 2 Sheds-Sheet 1 INVENTOR.

fl vajfzflan ATTOR .E'Y

Aug. 26 1924.

A. VALTMAN LATHE DOG Filed July 28.

1923 2 Sheets-Shem. 2

R m m m Patented Aug. 26, 1924.

UNITED STATES PATENT OFFICE.

ANTON VAL'IMAN, OF BOVEY, MINNESOTA, ASSIGNDR OF ONE-HALF TO HENRYVOLKE, OF BOVEY, MINNESOTA.

LATHE DOG.

Application filed July 28, 1923. Serial No. 654,376.

To all whom it may concern:

Be it known that I, ANTON VALTMAN, a citizen of the United States,residing at Bovey, in the county of Itasca and State of Minnesota, haveinvented certain new and useful Improvements in Lathe Dogs, of which thefollowing is a specification, refer- ,ence being had to the accompanyingdrawlngs.

This invention relates to lathe dogs and more particularly to auniversal lathe dog.

An important object of the invention is to provide a device of thischaracter in which the work may be inserted and tightened by hand andwhich by its engagement in the machine maintains the work in adjustedposition.

A further object of the invention is to provide a device of thischaracter which may be very cheaply produced and which will be durableand efficient in service.

A further object of the invention it to provide in a device of thischaracter a releasable latch holding the work in adjusted position untilthe same is engaged in the machine.

These and other objects I attain by the construction shown in theaccompanying drawings, wherein for the purpose of illustration is showna preferred embodiment of my invention and Wherein:

Figure 1 is a front elevation showing a universal lathe dog constructedin accordance with my invention applied to the face plate of .a lathe,the face plate being indicated in dotted lines;

Figure2 is an enlarged sectional view therethro-ugh Figure 3 is asectional view of the cup or slotted plate;

Figure 1 is a detail view partially in section showing the lockingdevice;

Figure 5 is a front elevation of the cagn plate detached;

Figure '6 is a side elevation of the cam plate detached; and

Figure 7 is a rear elevation of the cup plate.

Referring now more particularly to the drawings, the numeral 10indicates a cam plate proper, comprising a disk having an extension 11at one side thereof provided at its end with an angular member 12 for engagement in the slot 13 of the face plate 14:

disposed slots 19 formed therein for a purpose presently to appear. Inconjunction with the structure hereinbefore set forth I provide a capmember 20 comprising a carrier disk 21 having a central opening 22 andhaving upstanding flanges formed at one side thereof at the edge of theopening 22, as indicated at 23, and at the periphery thereof, asindicated at '24:, the flange 23 be ing of greater length than theflange 2 k and having its inner end externally screw threaded, asindicated at 25. The edge of the flange 24 slidably abuts the surface ofthe plate 10 about the edges thereof, the internal diameter of thisflange is such that it slidably engages against the edge of the plate 17The flange 23 extends through the openings 18 and 15 of the plates 17and 10 and serves to maintain the cap in proper position upon the camplate 10. The opening or bore 15 of the dogging plate is counterbored,as at 15, at the inner end thereof to form a seat for a locking ring 26which is threaded for engagement with the inner end of the flange 25.The plate 21 of the cup is provided in its inner face with radiallydirected channels 27 corresponding in number and arrangement to theslots 19 of the plate 17, the inner ends of these slots aligning withopenings 28 formed in the flange 23 of the cup. In these channels areslidably disposed gripping members 29, the inner ends of which areprovided with angular extensions 30 disposed at an angle to the body ofthe locking member 29 corresponding to the angle of the slots 19 of theplate 17.

The flange 24 of the cup is provided with a notch 31, one wall of whichis formed by an abrupt shoulder 32 and the other wall of which is in theform of a shallow incline gradually merging with the inner edge of theflange. The plate 10 and. the extension 11 thereof are provided in theirouter face with a radially directed slot 84 in which. is slidablymounted a key member 35 which tapers from its inner end to its outer endand which has its outer face inclined transversely to correspond to theinclination of the wall 33 of the notch 31. This locking member isnormally urged outwardly in the slot by means of a spring 36 mountedupon a post 37 carried by the plate 10 and having one end thereofengaged in the locking memher, the outer end of the locking member isprovided with a finger piece 38 by means of which the locking member maybe forced inwardly.

In assembling the device the members 29 are arrangedin their respectivechannels and the plate 10 is applied to the cup 20, the angular ends ofthe locking members 29 entering the slots 19 of the plate 17. Thelocking ring 26 is then placed in position and tightened. The disk 10and cup 20 are now relatively rotatable and it will be obvious that uponsuch rotation the engagement. of the annular ends 30 of the lockingmembers 29 in the slots 19 of the plates 17 will cause the lockingmembers 29 to be projected into or withdrawn from the opening 22 of thecup member, depending upon the direction of rotation. It will be obviousthat by relatively rotating the cam plate and cup these locking memberscan be shifted to bring their ends into engagement with a piece of metalM to be held in position in the machine. When the metal is properlygripped the latch member 35, which is held depressed through its fingerpiece 38 during the operation of engaging the metal in the dog, isreleased, springing upwardly and engaging the wall 33 of the slot toprevent relative rotation of the cam plate and cup. It will be obviousthat metal thus gripped is held positioned by a meansstationary withregards to the cup. It will be noted that the slots 19 of the plate 17are so formed that upon counterclockwise movement of the cam plate withrelation to the cup, the locking members 29 are forced into the bore 220f the cup. To those familiar with the art it is well known that themovement of a lathe, as regards the face plate thereof, iscounterclockwise and since the power applied by the tool will have thetendency to maintain the work and, accordingly, the cup 20 stationary,there will constantly be a tendency toward relative counterclockwisemovement of the cam plate 10, with the result that at all times duringthe operation of the machine, when a cut is being made, the operation ofthe machine itself tends to tighten the dog upon the work. Accordingly,it will be unnecessary for the operator to, do any more than making acasual tightening of the work in the machine, it being sufficient ifthis tightening is merely to an extent where it causes the lockingmembers 29 to exercise a dragging effect upon the cup, permitting suchtightening movement of the cam plate with relation thereto. It willfurthermore be obvious that the construction of the device ashereinbefore set forth is capable of some change and modificationwithout materially departing from the spirit of my invention and laccordingly do not limit myself to such specific structure except ashereinafter claimed.

I claim 1. A universal lathe dog including an apertured cam plate, aslotted plate carried by the cam plate and having an aperture aligningwith the aperture thereof, a carrier plate opposing the last named plateand provided in its face with radially extending channels, said carrierplate having tubular means engaging through the apertures of I slots ofsaid slotted tures of the first namedplates permitting I relativerotation thereof with relation to the first named plates for preventingseparation of the plates, and locking members slidably mounted in thechannels of said carrier plate and having angular'portions engaging incorrespondlng slots of said slotted plate, and alatch member carried bythe cam plate and engageable with the carrier plate when in one positionto prevent rotation thereof,with'relation to the cam plate.

3; A universal lathe dog including an" apertured cam plate, a slottedplate carried I by the cam plate and having an aperture aligning withthe aperture thereof, a carrier plate opposing the last named plate andprovided in its face with radially extending channels, said carrierplate having "tubular means engaging through the apertures of the firstnamed plates permitting relative rotation thereof with relation to thefirst named plates for preventing separation of the plates, and lockingmembersslidably mounted in the channels of said carrier'plate and havingangular portions engaging in corresponding slots of said slotted plate,and a latch member carried by the cam plate and engageable with thecarrier plate when in one position to prevent rotation thereof withrelation to-the cam plate,-and means connecting said latch member andcam plate yieldably urging the latch member to said position.

4. A universal lathe dog including an apertured cam plate, a slottedplate carried by the cam plate and having an aperture aligning with theaperture thereof, a carrier plate opposing the last named plate andprovided in its face with radially extending channels, said carrierplate having tubular means engaging through the apertures of the firstnamed plates permitting relative rotation thereof with relation to thefirst named plates for preventing separation of the plates, and lockingmembers slidably mounted in the channels of said carrier plate andhaving angular portions engaging in corresponding slots of said slottedplate, and a latch member carried by the cam plate and engageable withthe carrier plate when in one position to prevent rotation thereof withrelation to the cam plate, and means connecting said latch member andcam plate yieldably urging the latch member to said position, saidcarrier plate being provided with a peripheral flange abutting with itsinner end the adjacent face of the cam plate, the internal diameter ofsaid flange being such that it slidably engages the periphery of saidslotted plate.

5. A universal lathe dog including an apertured cam plate, a slottedplate carried by the cam plate and having an aperture aligning with theaperture thereof, a carrier plate opposing the last named plate andprovided in its face with radially extending channels, said carrierplate having tubular means engaging through the apertures of the firstnamed plates permitting relative rotation thereof with relation to thefirst named plates for preventing separation of the plates, lockingmembers slidably mounted in the channels of said carrier plate andhaving angular portions engaging in corresponding slots of said slottedplate, and means for locking the carrier plate to prevent rotationthereof with relation to the cam plate.

6. A universal lathe dog including an apertured cam plate, an aperturedslotted plate carried by the cam plate, a carrier plate opposing thelast named plate and provided in its face with radially extend ingchannels and having means extending through the apertures of the firstnamed plates permitting rotation thereof with relation to the firstnamed plates but preventing separation of the plates, and lockingmembers mounted in the channels of said carrier plate and havingportions engaging in corresponding slots of the slotted plate.

7. A universal lathe dog including an apertured cam plate, an aperturedslotted plate carried by the cam plate, a carrier plate opposing thelast named plate and provided in its face with radially extendingchannels and having means extending through the apertures of the firstnamed plates permitting rotation thereof with relation to the firstnamed plates but preventing separation of the plates, locking membersmounted in the channels of said carrier plate and having portionsengaging in corresponding slots of the slotted plate, and means forlatching the carrier plate against rotation with relation to the camplate.

In testimony whereof I hereunto aflix my signature.

ANTON VALTMAN.

